Interannual and long term variability of low level jetstream of the Asian summer monsoon
Interannual and long-term variability of the low level jetstream (LLJ) of the Asian summer monsoon during June to September was studied using reanalysis wind data. In order to study the variability, the domain of the LLJ covering the Indian and west Pacific Oceans was divided into six regions (boxes...
Main Authors: | , , , |
---|---|
Format: | Article |
Language: | English |
Published: |
Taylor & Francis Group
2018-01-01
|
Series: | Tellus: Series A, Dynamic Meteorology and Oceanography |
Subjects: | |
Online Access: | http://dx.doi.org/10.1080/16000870.2018.1445380 |
id |
doaj-6dc4cfef288a499ab4abc23e06f54b08 |
---|---|
record_format |
Article |
spelling |
doaj-6dc4cfef288a499ab4abc23e06f54b082020-11-25T02:07:50ZengTaylor & Francis GroupTellus: Series A, Dynamic Meteorology and Oceanography1600-08702018-01-017011910.1080/16000870.2018.14453801445380Interannual and long term variability of low level jetstream of the Asian summer monsoonShinu Sheela Wilson0P. V. Joseph1K. Mohanakumar2Ola M. Johannessen3Nansen Environmental Research Centre IndiaNansen Environmental Research Centre IndiaCochin University of Science and TechnologyNansen Scientific SocietyInterannual and long-term variability of the low level jetstream (LLJ) of the Asian summer monsoon during June to September was studied using reanalysis wind data. In order to study the variability, the domain of the LLJ covering the Indian and west Pacific Oceans was divided into six regions (boxes) based on their physical characteristics. The long term variability of LLJ and its relation with Indian monsoon rainfall and El Nino index were analysed. The low level circulation over Indian Ocean becomes weak during the positive phase of El Nino Southern Oscillation leads to warmer sea surface temperature over Indian Ocean. The strength of the low level jet over India depends on the convective heating of the atmosphere and not on the strength of the south Indian Ocean trade wind (ITz) which remains a passive component of the LLJ. The LLJ flow through peninsular India is weaker and the flow south of peninsular India is stronger during the recent decades in association with increasing number of break monsoon days. The cross equatorial flow over west Pacific Ocean has statistically significant increasing trend related to the increasing convection in the west Pacific Ocean.http://dx.doi.org/10.1080/16000870.2018.1445380low level jetstreamIndian Summer Monsoon Rainfall (ISMR)El Nino IndexInter-annual variability |
collection |
DOAJ |
language |
English |
format |
Article |
sources |
DOAJ |
author |
Shinu Sheela Wilson P. V. Joseph K. Mohanakumar Ola M. Johannessen |
spellingShingle |
Shinu Sheela Wilson P. V. Joseph K. Mohanakumar Ola M. Johannessen Interannual and long term variability of low level jetstream of the Asian summer monsoon Tellus: Series A, Dynamic Meteorology and Oceanography low level jetstream Indian Summer Monsoon Rainfall (ISMR) El Nino Index Inter-annual variability |
author_facet |
Shinu Sheela Wilson P. V. Joseph K. Mohanakumar Ola M. Johannessen |
author_sort |
Shinu Sheela Wilson |
title |
Interannual and long term variability of low level jetstream of the Asian summer monsoon |
title_short |
Interannual and long term variability of low level jetstream of the Asian summer monsoon |
title_full |
Interannual and long term variability of low level jetstream of the Asian summer monsoon |
title_fullStr |
Interannual and long term variability of low level jetstream of the Asian summer monsoon |
title_full_unstemmed |
Interannual and long term variability of low level jetstream of the Asian summer monsoon |
title_sort |
interannual and long term variability of low level jetstream of the asian summer monsoon |
publisher |
Taylor & Francis Group |
series |
Tellus: Series A, Dynamic Meteorology and Oceanography |
issn |
1600-0870 |
publishDate |
2018-01-01 |
description |
Interannual and long-term variability of the low level jetstream (LLJ) of the Asian summer monsoon during June to September was studied using reanalysis wind data. In order to study the variability, the domain of the LLJ covering the Indian and west Pacific Oceans was divided into six regions (boxes) based on their physical characteristics. The long term variability of LLJ and its relation with Indian monsoon rainfall and El Nino index were analysed. The low level circulation over Indian Ocean becomes weak during the positive phase of El Nino Southern Oscillation leads to warmer sea surface temperature over Indian Ocean. The strength of the low level jet over India depends on the convective heating of the atmosphere and not on the strength of the south Indian Ocean trade wind (ITz) which remains a passive component of the LLJ. The LLJ flow through peninsular India is weaker and the flow south of peninsular India is stronger during the recent decades in association with increasing number of break monsoon days. The cross equatorial flow over west Pacific Ocean has statistically significant increasing trend related to the increasing convection in the west Pacific Ocean. |
topic |
low level jetstream Indian Summer Monsoon Rainfall (ISMR) El Nino Index Inter-annual variability |
url |
http://dx.doi.org/10.1080/16000870.2018.1445380 |
work_keys_str_mv |
AT shinusheelawilson interannualandlongtermvariabilityoflowleveljetstreamoftheasiansummermonsoon AT pvjoseph interannualandlongtermvariabilityoflowleveljetstreamoftheasiansummermonsoon AT kmohanakumar interannualandlongtermvariabilityoflowleveljetstreamoftheasiansummermonsoon AT olamjohannessen interannualandlongtermvariabilityoflowleveljetstreamoftheasiansummermonsoon |
_version_ |
1724929307463122944 |